Module:WikidataIdentifiers

-- Functions for use in retrieving Wikidata for use in templates that deal with identifiers -- getIdentifierQualifier returns the value of a qualifier for an Identifier

p = {}

-- getIdentifierQualifier returns the value of a qualifier for an Identifier -- such as 'Art UK artist ID', P1367 -- the assumption is that one value exists for the property -- and only one qualifier exists for that value -- Constraint violations for P1367 are at: -- https://www.wikidata.org/wiki/Wikidata:Database_reports/Constraint_violations/P1367#Single_value p.getIdentifierQualifier = function(frame) local propertyID = mw.text.trim(frame.args[1] or "")

-- The PropertyID of the qualifier -- whose value is to be returned is passed in named parameter |qual= local qualifierID = frame.args.qual

-- Can take a named parameter |qid which is the Wikidata ID for the article. -- This will not normally be used because it's an expensive call. local qid = frame.args.qid if qid and (#qid == 0) then qid = nil end

local entity = mw.wikibase.getEntityObject(qid) local props if entity and entity.claims then props = entity.claims[propertyID] end if props then -- Check that the first value of the property is an external id if props[1].mainsnak.datatype == "external-id" then -- get any qualifiers of the first value of the property local quals = props[1].qualifiers if quals and quals[qualifierID] then -- check what the dataype of the first qualifier value is -- if it's quantity return the amount if quals[qualifierID][1].datatype == "quantity" then return tonumber(quals[qualifierID][1].datavalue.value.amount) end -- checks for other datatypes go here:

end end end end


return p